


FMA Steven Universe/Gem AU Outline

by Jeminy3



Series: AUs and Outlines [1]
Category: Fullmetal Alchemist - All Media Types, Fullmetal Alchemist: Brotherhood & Manga
Genre: Alternate Universe - Crystal Gems (Steven Universe), Alternate Universe - Steven Universe Fusion, Other, Steven Universe References
Language: English
Status: Completed
Published: 2019-03-09
Updated: 2019-03-09
Packaged: 2019-11-14 14:28:07
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,102
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18054236
Author URL: https://archiveofourown.org/users/Jeminy3/pseuds/Jeminy3
Summary: A repost from my Google Docs to make my AU ideas easier to find and access. This is a general outline of ideas, forever WIP and not going to be a proper fic at any point. Feel free to take inspiration from it, and if you draw/write anything based on it, feel free to link back to this and show me what you made!Read the doc hereThe Google Doc may be more subject to change from this version since it's easier to edit.For more reblogs, art and writing on this au, check out the tag on my tumblr blog:Click Here





	FMA Steven Universe/Gem AU Outline

FMA Steven Universe Crossover/FMA Gemverse

Name: Fullmetal Gem-mancer ?

Hundreds of years ago, Gems invaded the planet to use its resources. Diplomats recommended keeping its local humans and ecosystems alive for maximum benefit, so the Gems put its humans under a tyrannical rule for years.

eventually, a yellow gem who grew to sympathize with humans (Hohenheim), with help from a Xerxesian slave (Father), gave the humans access to their technology and formed a powerful rebel force to negotiate with the Gems and create peace between the two races. they meet mixed success, but create a tenuous peace. Xerxes, the most advanced country at the time, is at the epicenter of this.

when Homeworld receives word of what's happened and misinterpret it, they send a new mothership of invading gems to re-establish control. Hohenheim and the rebels work quickly to communicate the truth to them, but to no avail. Father suggests that only a show of force will convince Homeworld to leave them alone.

desperate, they steal the Gems' secret technique of creating a Perfect Cluster (Philosopher's Stone) and prepare to use it against the mothership, floating above the country of Xerxes. they plan to only sacrifice the warrior gems aboard the ship and incorporate their souls within Father or Hohenheim to disarm the invading forces.

but Father, hungry for power and wanting revenge against both the invading gems and the country who enslaved him, tricks everyone and makes everything on the ship and in Xerxes, human and gem alike, fodder for the Cluster. Wanting Hohenheim to share in his revenge, the power is divided evenly between them. Father absorbs mostly gem souls, while Hohenheim absorbs mostly human/ animal souls. An advanced civilization AND a powerful Gem ship are destroyed in one night, and any hope for peace between the races is obliterated.

horrified, Hohenheim argues with Father, then separates from him. both of them disappear into the annals of history as the remaining survivors pick up the pieces.

From then on, the ruins of Xerxes are well-known for being a long stretch of desert dotted with both Xerxesian ruins and the remains of a massive Gem ship. Both were equally pilfered by grave robbers to steal their secrets.

\---

For the next century or so, humans use the Gem tech they've borrowed to jumpstart their technological progress, developing advanced tech and weapons (Alchemy powers and Automail). Over time they destroy the remaining Gem holdouts and ships remaining on the planet, stranding whatever gems are left and forcing them to go into hiding in the wilderness or among human society.

From then until the present, Gems are heavily discriminated against, often to the point of hunting them down to either shatter them or trap them in bubble prisons. Gems who incorporate into human society find ways of perma-shifting their bodies to appear human and live fairly peaceful lives among them. some gems even form close relationships with humans, and in rare cases, are daring enough to sacrifice their bodies to produce human/gem hybrid offspring that carry their gems and powers. They hope their children will rise above the discrimination and help create peace between gems and humans again.

Father goes West and eventually founds the country of Amestris, planning to use it to make himself the most powerful Cluster in the universe, strong enough to destroy whatever forces Homeworld sends again, even Homeworld itself. To help him, he creates smaller Clusters from his blood, who become the Homonculi.

Hohenheim goes East and eventually becomes the legendary Great Sage of Xing, sharing techniques that develop Xing's medicine-based magic and tech into the best in the world.

\---

Hohenheim travels the world until he meets Trisha Elric in Resembool. They marry and settle down in the countryside next to the Rockbell family, who are human doctors and automail mechanics. When Trisha wants to have children together, Hohenheim uses the souls inside him to create two human/gem boys for them to raise together. He gives them the souls of two human brothers from Xerxes and the gems of two powerful Gold Zircon guards, hoping they will become forces for peace between humans and gems in the future. They name them Edward and Alphonse.

Unfortunately, when the boys are toddlers, Hohenheim learns of Father and his plans for the future, and is forced to leave his family to begin preparations to stop it from happening. Trisha promises to wait for him.

\---

Ishval is a region of PoC humans who've developed a community that fosters peace and community between humans, gems, and hybrids. They have tension with the Amestrian government for years until the fateful event that kicks off the Ishvalan Civil War, where a hybrid Ishvalan child is murdered by an Amestrian soldier (Envy). The war rages for seven years until the State Alchemists/Gem-mancers are brought in to bring it to a swift and bloody end, killing and shattering Ishvalans and Gems and scattering the survivors to refugee camps across the country. other casualties are Winry's parents at the hands of Scar.

Among them was the Flame User Roy Mustang, secretly a gem Hybrid himself. this is only known to his close human friends Riza Hawkeye and Maes Hughes. the war traumatizes him but gives him the idea to rise to the rank of Fuhrer, where he can change his country for the better and protect everyone, human and gem alike.

\---

over the next decade, Trisha's sons grow into good-hearted boys with impressive Gem Magic. They rarely show their gems or powers among the people of Resembool because Trisha knows from Hohenheim how humans still hate Gems and will probably feel the same toward human/gem hybrids. But generally, the few people who know, like the Rockbells, are chill about it and accept them.

But tragedy strikes again when Trisha succumbs to illness and dies suddenly. heartbroken, the boys vow to find a way to bring her back to life using their powers and the technology/research left behind in their father's study/basement. Years of studying on their own yield no results however, and they hit a dead end.

One day a strange woman named Izumi Curtis arrives in their town and helps stop a massive flood with what they know is Gem Magic. They beg her to take them on as apprentices, revealing themselves as human/gem hybrids who want to learn more and become stronger in the wake of their tragedy. Despite some reservations, she agrees, and takes them back home with her to Dublith. She reveals herself as a Gem, Smoky Quartz/Tiger's Eye, a quartz-based ex-Warrior-Gem created on the planet during the Invasion. She survived Xerxes and dodged capture by incorporating into human society about a century ago. She's been travelling for years to evade suspicion since she doesn't age, and even lived in Ishval briefly, escaping when the war broke out. Now she is a housewife who occasionally travels around to help people with her powers.

She warns against the dangers of experimenting with Forbidden Gem Magic/Tech in the realm of human/gem life, because years ago she attempted a ritual/experiment to give herself a body that would let her bear children without sacrificing herself and leaving her beloved husband behind. But it backfired and damaged her gem beyond repair, crippling her powers and making her unstable. She challenges Ed and Al so they learn the importance of life on this planet and the place Gemkind can have in it, and when they pass, she teaches them all she knows, including the history of the Gem Invasion, the Tragedy at Xerxes, and the remaining Gems on the planet and the struggles they face now. Despite their mixed race, she implores that they hide their gems among humans unless they prove trustworthy.

She also teaches them to fight and summon Gem Weapons. Ed can summon a sword while Al can summon a shield.

\---

Months later, Ed and Al return home to Resembool, and with what they've learned and Hohenheim's tech in the basement, prepare the Gem Ritual/Experiment to bring their mother back to life. they figure it'll work since they're performing it on a human body and not themselves.

Unfortunately, it doesn't work. The ensuing backfire causes an explosion of energy that partially destroys their house, completely destroys their mother's body, and permanently damages their own bodies. Edward loses an arm and a leg that he can't regenerate, while Alphonse is reduced to his gem and can't reform his body at all. Both of their gems are now cracked, crippling their powers. Desperate, Ed places Al's gem inside a robotic gem body in the basement, bringing him back in some form, then collapses from pain/blood loss. Al carries him to the Rockbell house, where they explain what happened to Pinako and Winry and try to recover.

\---

A few days later, Colonel Mustang and Lieutenant Hawkeye arrive to investigate reports of an explosion and a tip about a user of Gem Magic/Tech named Edward Elric. Instead they find a ruined house, a crippled boy, and a sentient gem robot. After learning what's happened, that the boys are gem hybrids and orphans who just wanted their mother back (how they were born without their gem parent sacrificing themself is a mystery that died with Trisha), Mustang sympathizes with them and reveals his own secret of being a Hybrid as well. He offers Edward a position as a State Alchemist/Mancer under his command, where he can use the State's resources to find a way to restore their bodies, especially for Alphonse. Ed agrees, when he's able to stand on his own again.

After Mustang and Hawkeye leave, Ed begs Pinako and Winry to give him gem automail limbs so he can join the State. Eventually they agree. With Ed being part-gem and the tech being more highly advanced, the procedure is painful, but not as badly as canon verse. He's given two years to recover but does it in one.

\---

A year later, Ed is recovered and ready to go to East City. Before they leave, Ed and Al burn down the remains of their house (which was mostly destroyed anyway) to motivate themselves to never turn back.

Ed and Al meet with Mustang again at East Headquarters, and have Mustang escort Ed to Central for his State test. there, Ed demonstrates the gem powers he has left, incorporated into and enhanced with his automail to divert from the fact that he has a gem. He passes and becomes a State Alchemist/Mancer, given the title of Fullmetal Gem-mancer.

\---

Ed and Al spend the next several years travelling the country following leads on the elusive Cluster, a mysterious unknown gemstone containing immense power, possibly enough to restore their bodies.

The rest follows canon events with some differences, since Alchemy is now Gem Magic/Tech and Alchemy/Alkehestry Users are either humans using Gem Tech, Gems, or Hybrids.

Notes/Ideas:

\- The aesthetic created here would be interesting because its 18-19th century Europe going through an industrial revolution via highly advanced alien technology based on light and gemstones. Any geometric patterns that keep popping up, like Diamond symbols, are only left in 'cause the humans thought they looked cool.

\- No one knows what destroyed Xerxes and the Gem Mothership until Hohenheim reappears. Any surviving Gems, like Izumi, basically watched it happen from the outskirts.

\- Ed's automail would probably look and function a lot like old-Peridot's cybernetic limbs. Same with Alphonse's robot body.

\- As kids, Ed and Al could fuse into a larger, more powerful form of their gems, Gold Zircon. they can't anymore. Also can't summon their weapons without a lot of effort/willpower.

\- Ed thinks he can't fuse anymore, but with a lot of training and effort, he can with [insert shipping partner here]

\- Roy can probably fuse with Riza or Hughes, if they're up for it.

\- If ever, a Roy/Riza fusion would most likely happen while they're fighting the zombie-things together during the Promised Day. But once they face down Envy and they reveal themselves as Hughes' killer, Roy unfuses to go into his Rage Mode.

\- In contrast to Roy/Riza, a Hughes/Roy fusion would’ve happened in a very casual context, probably in their academy days. they got a bit drunk and danced terribly on a day off, and, platonically or romantically, got really into it, to the point that Roy’s gem activated and they fused accidentally. If this was Hughes’ way of discovering that Roy wasn’t fully human, it’s a very shocking surprise and makes him freak out and break out of the fusion right away. Roy freaks out just as much since he was still learning about Gem stuff and probably didn't even know he could fuse with humans.

After that passes, or in the cases that Hughes already knew or was very chill about it, they spend the day just messing around in their fused form, relaxing and enjoying the experience. They go around campus confusing their friends and convincing them they’re a new student named “Hustang” or something equally ridiculous.

In the years later it’s something they still do occasionally for fun, but after Ishval, Roy isn’t really up for it for a while. That doesn’t stop Hughes from teasing him about it in privacy though.

They find time to do it again at least once before Hughes’ death.

\- Hybrids are sometimes partly influenced in their thoughts/personalities from subconscious feelings and memories coming from their parent's Gem. They always regret never being able to meet their Gem parent in some way.

\- Roy's mother, Onyx, was a quartz-based, high-ranking warrior Gem created on the planet during the Invasion who was instrumental in helping create peace during the Rebellion. she helped ensure safety for herself and other gems in her command in the wake of the Xerxes tragedy and helped them settle down among humans in Amestris. after getting married and seeing the warmongering path Amestris was taking, she decided to bear a hybrid child in hopes he would grow into a leader that could change Amestris' path.

\- Roy's ignition gloves are NOT his Gem Weapon. they're something he developed from Berthold's research on controlling fire through gem tech/magic. he actually has no idea how to summon his Weapon. his mother is gone and his father died before he could teach him much of anything about his Gem heritage, so all his knowledge and skills in Gem Magic come from studying under Gem-mancer Berthold and at the Academy. it probably only happens in a moment of desperation and surprises him just as much as everyone else, such as the Lust battle after his gloves are destroyed and him and Havoc are bleeding out.

\- Ling is a Hybrid, his mother being Black Opal/Spinel, another powerful Gem who survived the Invasion and Xerxes and went into hiding in Xing, eventually getting adopted by the Yao clan. When selected as a concubine for the Emperor, she enacted a cunning plan to bear a child with her lover, go to the Palace, disappear into the Stone, and pass the child off as a son of the Emperor. This was all in the hopes her child would succeed where the other heirs could not with the help of gem powers and become a great Emperor. he's ambitious and reckless doesn't hide his gem on his body or his gem powers, using it to enhance his fighting abilities and intimidate the other heirs, goading them into fighting him so he can defeat them. Lan Fan and Fuu are humans.

\- Mei is probably a human skilled in using artificial Gem Magic and technically, a more qualified heir to the Emperor's throne.

\- Scar's powers come from either gem tattoos, gem tech that he wears on his arm, or his arm is made of gem tech/magic. either way they were developed by his brother, whose research also leads to the ritual that will undo the nationwide Cluster ritual.

\- Ed and Ling learn to fuse in Gluttony's Stomach Dimension to survive fighting Envy. They either escape in their fused form and no one recognizes them so they can escape, OR (more likely) they take too much damage and unfuse during the fight and follow canon events until they're brought before Father. Ling accepts the offer of absorbing Greed's Cluster and becomes Greedling.

\---

\- Olivier is also secretly a gem. The eye hidden under her hair is also hidden under an eyepatch, because her gem replaces her right eye.

She’s a rarity, since she was an invading Homeworld gem who was always a tough, cold-hearted General. She was stranded on the planet when, after the fall of Xerxes and the Mothership, her personal ship was brought down by humans over the northern mountains, where it’s remains were gutted and eventually used to build Fort Briggs on top of it.

Her army was either scattered or shattered. She herself was captured and, to humiliate her, was forcibly Cracked to cripple her powers and make her a servant gem to any rich human family who wanted her. She passed between families for decades until she was finally purchased by the patriarch of the Armstrongs, who took pity on her and treated her like family, eventually adopting her as his eldest daughter. Her spirit was nearly broken but this revived it, and made her finally respect and care for the humans she once despised. She assimilated into human society as the eldest of the Armstrong siblings, became a soldier, rose through the ranks, and finally earned her place as a General again, taking command of Fort Briggs and the remains of her ship. Only her closest subordinates know her secret, and a few of her soldiers are surviving gems from her old army that she’s found and reunited with.

When Ed and Al arrive at Briggs and eventually divulge the truth about the nationwide conspiracy and the Clusters, she’s keen to help them thwart it to protect the planet that’s now her home, and empathizes with their Cracked condition. Although she’s still lukewarm to humans who aren’t her adopted family, and even with them she can be harsh (see: Alex) She almost never refers to herself as her Gem name anymore.

If Olivier learns that Roy is the son of Onyx and has her gem, she comments on the coincidence, since she once faced General Onyx during the Rebellion and respected her tactics. She acknowledges Roy’s natural-born leadership but says he has a long way to go to succeed his mother as just a Colonel. Roy (after recovering from the surprise) says that’s the plan.


End file.
